To do this, it makes sense to treat legacy guards as a separate
guard_selection_t *, and handle them separately. This also means we
add support here for having multiple guard selections.
Note that we don't persist pathbias information yet; that will take
some refactoring.
This patch doesn't cover every case; omitted cases are marked with
"XXXX prop271", as usual. It leaves both the old interface and the
new interface for guard status notification, since they don't
actually work in the same way: the new API wants to be told when a
circuit has failed or succeeded, whereas the old API wants to know
when a channel has failed or succeeded.
I ran into some trouble with directory guard stuff, since when we
pick the directory guard, we don't actually have a circuit to
associate it with. I solved that by allowing guard states to be
associated with directory connections, not just circuits.
I expect we'll be ripping this out somewhere in 0.3.0, but let's
keep it around for a little while in case it turns out to be the
only way to avert disaster?
This state corresponds to the WAITING_FOR_BETTER_GUARD state; it's
for circuits that are 100% constructed, but which we won't use until
we are sure that we wouldn't use circuits with a better guard.
When a nonprimary guard's circuit is complete, we don't call it
actually usable until we are pretty sure that every better guard
is indeed not going to give us a working circuit.
Here we add a little bit of state to origin circuits, and set up
the necessary functions for the circuit code to call in order to
find guards, use guards, and decide when circuits can be used.
There's also an incomplete function for the hard part of the
circuit-maintenance code, where we figure out whether any waiting
guards are ready to become usable.
(This patch finally uses the handle.c code to make safe handles to
entry_guard_t objects, so that we are allowed to free an
entry_guard_t without checking whether any origin_circuit_t is
holding a reference to it.)
This code handles:
* Maintaining the sampled set, the filtered set, and the
usable_filtered set.
* Maintaining the confirmed and primary guard lists.
* Picking guards for circuits, and updating guard state when
circuit state changes.
Additionally, I've done code structure movement: even more constants
and structures from entrynodes.c have become ENTRYNODES_PRIVATE
fields of entrynodes.h.
I've also included a bunch of documentation and a bunch of unit
tests. Coverage on the new code is pretty high.
I've noted important things to resolve before this branch is done
with the /XXXX.*prop271/ regex.
These are taken from the proposal, and defined there. Some of them
should turn into consensus parameters.
Also, remove some dead code that was there to make compilation work,
and use ATTR_UNUSED like a normal person.
The previous commit, in moving a bunch of functions to bridges.c,
broke compilation because bridges.c required two entry points to
entrynodes.c it didn't have.
This patch is just:
* Code movement
* Adding headers here and there as needed
* Adding a bridges_free_all() with a call to it.
It breaks compilation, since the bridge code needed to make exactly
2 calls into entrynodes.c internals. I'll fix those in the next
commit.
The encoding code is very straightforward. The decoding code is a
bit tricky, but clean-ish. The sampling code is untested and
probably needs more work.
This was a relatively mechanical change. First, I added an accessor
function for the pathbias-state field of a guard. Then I did a
search-and-replace in circpathbias.c to replace "guard->pb." with
"pb->". Finally, I made sure that "pb" was declared whenever it was
needed.
The entry_guard_t structure should really be opaque, so that we
can change its contents and have the rest of Tor not care.
This commit makes it "mostly opaque" -- circpathbias.c can still see
inside it. (I'm making circpathbias.c exempt since it's the only
part of Tor outside of entrynodes.c that made serious use of
entry_guard_t internals.)
This affects clients with FetchUselessDescriptors 1.
It might also cause subtle bugs on directory mirrors and authorities,
causing them to consider all full descriptors as failed or old.
Improve the messages logged when Tor wants or needs to load the master ed25519 identity key so the user is explicitly informed when further action is required or not. Fixes ticket #20650.
Apple is supposed to decorate their function declarations with
macros to indicate which OSX version introduced them, so that you
can tell the compiler that you want to build against certain
versions of OSX. But they forgot to do that for clock_gettime() and
getentropy(), both of which they introduced in 10.12.
This patch adds a kludge to the configure.ac script where, if we
detect that we are targeting OSX 10.11 or earlier, we don't even probe
to see if the two offending functions are present.
Closes ticket 20235.